X# (pronounced X-sharp) is an XML-oriented programming language designed to quickly create Web applications and services. Everything is represented as an XML tree, and instead of using functions to manipulate information or perform actions, all possible operations are done by adding, removing, or changing nodes from this tree. Since there are no functions to learn and everything is done intuitively, even inexperienced developers can create complex Web applications and services quickly.
Gimp User Filter is a work-alike to Adobe's Filter Factory. It is a generic image processing plug-in that can be used to create new filters for The GIMP without having to go through the process of learning about The GIMP's SDK. Many freely available filters that have been created for Filter Factory can also be used with this plug-in.
Glulxe is an interpreted implementation of the Glulx portable Interactive Fiction VM, like the Z-machine but using the Glk API. Unlike the Z-machine, it uses 32-bit data and addresses, so it can handle game files up to four gigabytes long. Also unlike the Z-machine, it has native support for Glk I/O, so game files can use any capability Glk provides. However, like the Z-machine, you can write games in the Inform language and compile them to Glulx game files.
IPL stands for the Invocation Programming Language, a concurrent programming language described by Karl Fant in his book "Computer Science Reconsidered: The Invocation Model of Process Expression." This software comprises a C++ class hierarchy for representing language internals, a language parser, and a graphical editor and interpreter for experimenting with concurrent programs. In a sense, this is the software that could have been on a CD in the back of the book.